Message division communication method and communication system

Abstract

A message division communication method and system are disclosed for a communication system comprising a host, an intermediate device connected to the host through a high-speed bus and a remote device connected to the intermediate device or the host through a low-speed bus. A message is transmitted in such a manner that the host designates and notifies the remote device of a maximum message length determined in a way corresponding to the transmission rate of the low-speed bus and divides the message into division messages each not exceeding the maximum message length thereby to transmit and receive the division messages between the host and the remote device. Even with a communication system in which low-speed and high-speed buses coexist, a message can be transmitted and received by a common communication control scheme.

What is claimed is:  
     
       1. In a communication system comprising a host, an intermediate device connected to the host through a high-speed bus, and a remote device connected to a selected one of said intermediate device and said host through a low-speed bus, a message division communication method for transmitting a method, comprising the steps of: 
       designating and notifying from said host to said remote device of a maximum message length determined in a way corresponding to the transmission rate of said low-speed bus; and  
       dividing said message in a manner not to exceed the maximum message length designated into a plurality of division messages, and transmitting the plurality of division messages between said host and said remote device;  
       wherein said message includes a relative address section having a plurality of relative addresses and an entity section including a plurality of entities corresponding to said relative addresses, respectively, and wherein said message is transmitted by being divided into one of a plurality of entities corresponding to one of a plurality of relative addresses selected in the order defined in said relative address section in a manner not to exceed said maximum message length.